The Web Content Accessibility Guidelines Working Group is working carefully to enable organizations and individuals that are currently using WCAG 1.0 (which remains stable and referenceable at this time) to ensure that they will eventually be able to make a smooth transition to WCAG 2.0.

Checkpoint ID
WCAG 2.0 Working Draft (24 June 2003)
WCAG 1.0
text-equiv
Checkpoint: 1.1 [CORE] All non-text content that can be expressed in words has a text equivalent of the function or information that the non-text content was intended to convey. [was 1.1]

1.3 Until user agents can automatically read aloud the text equivalent of a visual track, provide an auditory description of the important information of the visual track of a multimedia presentation. [Priority 1]

1.4 For any time-based multimedia presentation (e.g., a movie or animation), synchronize equivalent alternatives (e.g., captions or auditory descriptions of the visual track) with the presentation. [Priority 1]

2.1 Ensure that all information conveyed with color is also available without color, for example from context or markup. [Priority 1]

3.3 Use style sheets to control layout and presentation. [Priority 2]

unambiguous-decoding
Checkpoint: 1.4 [CORE] All characters and words in the content can be unambiguously decoded. [was 1.6]Â
N/A
structure-emphasis
Checkpoint: 1.5 [EXTENDED] Structure has been made perceivable to more people through presentation(s), positioning, and labels. [was 1.4]

10.2 Until user agents support explicit associations between labels and form controls, for all form controls with implicitly associated labels, ensure that the label is properly positioned. [Priority 2]

2.2 Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen. [Priority 2 for images, Priority 3 for text].

keyboard-operation
Checkpoint: 2.1 [CORE] All functionality is operable at a minimum through a keyboard or a keyboard interface. [was 2.1]

time-limits
Checkpoint: 2.2 [CORE] Users can control any time limits on their reading, interaction, or responses unless control is not possible due to nature of real time events or competition. [was 2.2]

7.2 Until user agents allow users to control blinking, avoid causing content to blink (i.e., change presentation at a regular rate, such as turning on and off). [Priority 2]

3.7 Mark up quotations. Do not use quotation markup for formatting effects such as indentation. [Priority 2]

5.3 Do not use tables for layout unless the table makes sense when linearized. Otherwise, if the table does not make sense, provide an alternative equivalent (which may be a linearized version). [Priority 2]

5.4 If a table is used for layout, do not use any structural markup for the purpose of visual formatting. [Priority 2]

11.2 Avoid deprecated features of W3C technologies. [Priority 2]

declare-technology
Checkpoint: 4.2 [EXTENDED] Technologies that are relied upon by the content are declared and widely available.[was 5.2]Â Â

6.1 Organize documents so they may be read without style sheets. For example, when an HTML document is rendered without associated style sheets, it must still be possible to read the document. [Priority 1]

6.3 Ensure that pages are usable when scripts, applets, or other programmatic objects are turned off or not supported. If this is not possible, provide equivalent information on an alternative accessible page. [Priority 1]

6.5 Ensure that dynamic content is accessible or provide an alternative presentation or page. [Priority 2]

10.3 Until user agents (including assistive technologies) render side-by-side text correctly, provide a linear text alternative (on the current page or some other) for all tables that lay out text in parallel, word-wrapped columns. [Priority 3]

11.4 If, after best efforts, you cannot create an accessible page, provide a link to an alternative page that uses W3C technologies, is accessible, has equivalent information (or functionality), and is updated as often as the inaccessible (original) page. [Priority 1]

technology-supports-access
Checkpoint: 4.3 [EXTENDED] Technologies used for presentation and user interface support accessibility or alternate versions of the content are provided that do support accessibility.[was 5.3 and 5.4]

3.1 When an appropriate markup language exists, use markup rather than images to convey information. [Priority 2]

8.1 Make programmatic elements such as scripts and applets directly accessible or compatible with assistive technologies [Priority 1 if functionality is important and not presented elsewhere, otherwise Priority 2.]

9.2 Ensure that any element that has its own interface can be operated in a device-independent manner. [Priority 2]

11.1 Use W3C technologies when they are available and appropriate for a task and use the latest versions when supported.

13.6 Group related links, identify the group (for user agents), and, until user agents do so, provide a way to bypass the group. [Priority 3]

13.10 Provide a means to skip over multi-line ASCII art. [Priority 3]

N/A
Server-side Techniques

6.2 Ensure that equivalents for dynamic content are updated when the dynamic content changes. [Priority 1]

11.3 Provide information so that users may receive documents according to their preferences (e.g., language, content type, etc.) [Priority 3]

Issues

In many cases, several WCAG 1.0 checkpoints of varying priority levels map to a single WCAG 2.0 checkpoint. How should we resolve the difference? Could this imply that we only prioritize at the technology-specific level?

There are several WCAG 1.0 checkpoints whose priority is under debate. For example, Len maintained that WCAG 1.0 checkpoint 5.3 (do not use tables for layout unless makes sense when linearized) is not a P2 but a P1.

There is at least one redundancy in WCAG 1.0 checkpoints. In one example, the new WCAG 2.0 checkpoint combines the redundant checkpoints. For example, WCAG 2.0 Working Draft Checkpoint 2.1 (Use device-independent event handlers). We said this twice in WCAG 1.0 with checkpoints 6.4 and 9.3.